All subjects will receive monthly phone calls to encourage maintaining a regular walking regimen. Walking activity will be monitored periodically using a pedometer. Subjects will receive knee MRIs and weight-bearing knee radiographs at the start and end of the study. All participants will complete pain evaluations and clinical knee score questionnaires during the study. The investigators expect that subjects in both groups will have a reduction in knee pain over the course of the 52-week intervention. The primary objective of the study it to determine if there is change in pain between baseline and week 52 is different between the two groups.